I watched this presentation and there's a section on how to build an IOS Maps like UI. When dragging from the bottom to top, it drags to the top, and after it reaches the top, it continues scrolling up. Also, when scrolling down, when it reached the top content of the ScrollView, it continues to drag down.
It is suggested that it can be done using ScrollView by adding an empty transparent cell as the first element on the ScrollView. I have tried implementing the same which can be found in this snack. In my case, instead of Maps, I am using another ScrollView.
But the problem is that the first element (transparent element) does not allow to interact with the First ScrollView elements. I have tried with pointerEvents inside the first transparent view and even in its parent ScrollView. But this does not help. Has anyone tried implementing this kind of use case with react-native? All I found was this library, but I think it's not maintained properly.
you need to set the z-index of the transparent view to send it under/behind the interactive content, here is a good resource:
https://philipwalton.com/articles/what-no-one-told-you-about-z-index/
Edit: Actually I could not accomplish it, it seems like everything inside a scrollview will always be behind or in front of other elements, it seems like you can't have part of the scrollview behind something else and another part in front of something else.
Related
In my application I want to create a couple animations on my FlatList.
For example, after fetching the data and feeding it to the list I want the items that should be visible to slide from the left. When I'm scrolling each item (at the top) that supposed to disappear will slide out to the right and each item that should appear (at the bottom) should slide from the left. Is it possible in React Native?
I only managed to create one type of animation - items sliding right when they are about to disappear, but I don't have any idea how to make the items to appear from the left.
My Animated.View can receive only one type of transform. So how can create different types of input/output ranges for the top and the bottom of the list?
I tried to find some examples on the internet but couldn't find any for multiple animations, only for one type.
I think you will find React Native Reanimated's Entering and Exiting Animations API
useful for this task. It greatly simplifies animations like this in my experience.
In case you want to get more control. Using a FlatList, you can also use its onScroll prop to get the current value for YOffset (contentOffset.y) via the Reanimated useAnimatedScrollHandler. Thus you can figure out how much has been scrolled.
Which you could then use to manually apply any translateX's required to the Animated.View of whatever items the flatlist is rendering. The logic you'll of course have to figure out though. But it's a start.
Be sure to do any animation interpolates using UI thread worklets on Reanimated only. Good luck!
I've been trying to implement a rather common UI pattern. I've got a react-navigation MaterialTopTabNavigator that contains a number of ListViews. When the currently active ListView is scrolled down, the header above the Tabs is supposed to be hidden (by translating it up, out of the viewport), the tabs should as well move up.
Like in this picture
The problem I'm facing here is either
a) if i translate the header and the tabs up, i need a paddingTop in the lists to make sure the first item is completely visible. But if i scroll down and the header is hidden and then switch to the next tab (where the list is scrolled to the top) the padding will be visible.
or
b) If i translate the whole thing (header, tabbar, and ListView) the paddingTop is not necessary (I can add a padding at the bottom and hide it via a BottomTabNavigator) but the animation gets jerky on android.
There seems to be a bug in react-native causing this.
But there are apps around for Android that implement this pattern.
I'd be grateful for any ideas or pointers around this.
In my app, I have horizontal FlatList which is used for swiping between several sub-pages of a screen. This works great.
However, on one of the pages, I have a Slider component. On iOS it works fine, but on Android, the parent ScrollView of the FlatList seems to "steal" the swipe gesture. I am only able to adjust the Slider by clicking very precisely on its thin line, but I cannot adjust it by sliding.
What I need is something like one of these
A view that wraps the Slider component and stops swipe gestures from being propagated to the parent ScrollView
A way to make the FlatList/ScrollView not consume swipes directly on elements that responds to horizontal swipes themself
Somehow adjust the area of which the Slider component will eat the touches around it (it's very small and hard to hit directly). I already tried adding a hitSlop prop, with no luck.
Any suggestions for a solution are very appreciated :)
Check example code and result here.
https://snack.expo.io/#esbenvb/mad-yogurt
I'm attempting to create a custom NavBar on a screen that renders a ScrollView. Inside the NavBar, there's a button, that when pressed, causes the NavBar to translate downwards, thereby giving the appearance that the NavBar is expanding (This is done using Animated.spring() with the useNativeDriver option). Everything is working great, except if the ScrollView is still scrolling at the time the button is tapped (ie: when "momentum" scroll is taking place). In this scenario, the onPress handler that kicks off the NavBar animation is invoked as expected, but calls to Animated.spring() do not cause any animation to take place. Is it possible to either have the NavBar "expansion" animation to occur during the scroll, or pause the scroll to allow animation to proceed?
Like it's explained in RN docs the animation type you using are stoped by gesture events like scrolling, better use Animated.event() with onScrollprops combined with an interpolation animation to animate you footer.
I am trying to create the same type of slide-up/pull-up menu (from the bottom) as the Any.do iPhone app, but not having any success.
The issue I am running into is the app was built with storyboards so I am thinking I might have to scratch that idea and use just code.
Any ideas?
There is no need to get rid of your storyboard to recreate this, that's what IBOutlets are for. Any way, it looks like this was made by creating a UIScrollView that takes up the entire screen. Then add a UITableView to the upper section of the scroll view. Mind you in order for this to work, you'll need to disable scrolling on the scroll view in the background.
From there you can programmatically add the other elements to the scroll view to be rendered off screen, since there are only three they can probably just be buttons. And finally, since scrolling is disabled on the background scroll view you can add an image with a UISwipeGestureRecognizer at the bottom of the screen to manually change the scroll view's content offset property.